The present invention relates generally to a focal point locator for a point source and more particularly to a beam finder for calibrating X-ray equipment.
An X-ray head commonly presents the operator with a visually opaque plastic lens through which X-rays are transmitted from a point source anode located behind the plastic lens inside the head. To minimize stray X-ray propagation outside the head, and to maximize the efficiency of the X-ray source, it is desirable to collimate the output by placing a lead shield over the plastic lens and providing a single hole through the shield at the focal point of the X-ray head. One method of determining the focal point involves the use of a multi-pinholed lead plate of one millimeter thickness, an x-y mechanical stage, a transparent methacrylate plate, a film cassette and a telescope. The invention provides the same measurement in a much less complicated manner.